Microsoft has released a new type for Environment Variables called secret. In this video I will take you through the process of adding an Environment Variable Secret and how to use them in Power Automate.
Environment Variables Docs:
https://docs.microsoft.com/en-us/powerapps/maker/data-platform/environmentvariables#use-azure-key-vault-secrets
Azure Key Vault best practices:
https://docs.microsoft.com/en-us/azure/key-vault/general/best-practices#use-separate-key-vaults